Drying, waste-heat recovery, and cooling system



'F. s. BOLTZ 1,731,290

WASTE HEAT RECOVERY, AND COOLING SYSTEM DRYING,

Filed Dec. 19, 1927 4 Sheets-Sheet 1 INVEN'J'E! V:

, 3M 625.044 y Mam 4Sheets-Sheet 2- F. S. BOLTZ Filed Dec. 19, 1927 DRYING, WASTE HEAT RECOVERY, AND COOLING SYSTEM Oct. 15, 1929.

' Oct; 15, 1929. F.'S. BOLTZ 1,731,290

DRYING, WASTE HEAT RECOVERY, AND COOLING SYSTEM 4 Sheets-Sheet Filed Dec. 19, 1927 Fl INVEN+EIVZ imdguu;

A-h ys Oct. 15,1929. s; BOLTZ 1,731,290

DRYING, WASTE HEAT RECOVERY, AND COOLING SYSTEM Filed Dec. 19, 1927 4 Sheets-Sheet 4 IN VEN+D 1 I.

Patented Oct. 15, 1929 PATENT OFFICE FRED S. IBOLTZ, OF MANSFIELD, MASSACHUSETTS DRYING, WAS'lIEl-IHIEAT RECOVERY, AN?) COOLING SYSTEM The invention relates to a new and useful improvement in a drying, waste heat recovery and cooling system. It is more especially intended for use in laundries and the like, but in many of its features it is applicable to other uses. It has special reference to drying and ventilating apparatus. One object of the invention is to dry the clothes or other articles witha minimum of labor and to save large quantities of heat in the humid air which are ordinarily allowed to escape out of doors and which by my invention may be utilized to aid in. heating the process water used in the wash wheels. 5 The humid air in laundries carries with it lint coming from the clothes and the discharge of this lint laden air around buildings is ob 'ectionable. Some machines havelint catchmg devices consisting of moving screens. It 2 is more or less difficult to keep these screens clean and in good operating condition. One object of the present invention is to provide spray mechanism for the lint laden air and cause the lint to be carried to a place where it can be conveniently disposed of. The water from the sprays catches the lint and deposits the lint on the copling surface which. is in the path of the lint laden air from where it flows by gravity to a tank adjacent the cold water coils.

The cooling coils thus utilized are .the ones which carry the fresh water to the washing machine. The spray water absorbs the heat of the warm lint laden air and when the spray 7 water thus warmed falls on the cooling coils.

it warms the 'coil' and the water which is passing through the coil. The spray'water thus heated by the warm humid air heats the coils by contact with them better than by contact 40 of the hot humid air itself with the coils.

' In laundries there are usually a. large number of heated drying machines of different kinds and the heated machines coming in contact with the damp clothes that are being 45.

or humidity of the air surrounding the machinery. If this warm humid air is not re .moved from the working areasit will soon become saturated with moisture and when the 60 saturated air comes in contact with cool surdried or finished will raise the temperature heating medium.

Application filed December 19, 1927. Serial No. 241,006.

faces the moisture in the air will collect and drop on the finished goods and do other damage. The usual method of removing this heated air is by drawing it out of the building by fans or blowers. The air thus removed is replaced by other air from the outside which is usually heated at an expenditure of steam either in radiators or finishing machines. One object of the invention is to remove this warm humid air and extract the heat from it for useful purposes either for heating the process water used in the washing or for any other useful purpose and to return it so that the cool air can again absorb heat and moisture escaping from themachinery.

l/Varm humid. air is drawn through .the water spray and over the cooling spray by a system of ducts and when the humid air is cooled it will deposit its moisture, that is, it will drip down when it comes in contact with the cold surfaces of the-apparatus and will have capacity to absorb and carry more moisture when heated again; When the humid air is cooledthe moisture content is lowered by reason of dripping and this leaves the clothes still saturated just short of the dripping I point. The cool saturated air when distributed around the hot finishing machinery will rise in temperature and the power for carrying moisture is increased. This air is so then able to absorb and carry away moisture that is, driven out of the clothes in' the drying or finishing process. v e

Drying in presses and flat work presses is usually done by bringing the clothes incontact with hot plates. y

In some forms of finishing it is more desirable' to let warm dry air pass throu h the clothes that are being dried, the warm air picking up the moisture. .In apparatus em- ,bodying my invention, after the air isdehumidified by the sprays and cooling-coils it is then reheated by heating "coils such as steam, air or hot water or any other suitable The power of this reheated air to absorb moisture is increased and this reheated air when passed through a drying tumbler will collect the moisture from the clothes that are being dried in the tumbler.

' ly rotate.

In connection with the apparatus. there is provided a storage tank for the water to be used in the washing. 'This tank may be. supplied as desired from the city main or other suitable source. The water is pumped from the lower part of this tank through the cooling coils and the water after passing through the cooling coils is pumped back intothe upper part of the storage tank.

Briefly, in the use of the apparatus, first, the warm humid air is cooled and the extracted heat is utilized to heat the coils which carry the fresh water. Second, the moisture is extracted from the air by cooling and the dry cool air is returned to the work rooms *where it can absorb more moisture from the humid air. Third, a part of the cooled dry air is distributed to furnish ventilation instead of taking fresh air from outside which has to be heated at expense by steam or otherwise. Fourth, the lint laden air is washed by the spray nozzles so that the lint is deposited leaving the air clean. Fifth, the air thus cleaned is heated and returned to again pass through the drying apparatus.

The invention will be fully understood from the following description when taken in connection with the accompanying drawings and the novel features thereof will be pointed out and clearly defined in the claims at the close of this specification.

- Fig. 1 is a plan view of apparatus embody ing my invention.

Fig. 2 is a front elevation of the parts shown in Fig. 1.

Fig. 3 is a section on the line 33,Fig. *2. Fig. 4 is an end elevation as viewed from the left of Fig. 2.

' Fig. 5 is a vertical longitudinal section of the drying tumbler taken on line 5-5, Fig. 2. Fig. 6 is a section taken on line 6-6, Fig. 5. -Fig. 7 is a section taken on line 7 7 Fig. 5. -Fig. 8 is a detail view of the tumbler cylinder through which the goods pass in drying.

Fig. 9 is a diagram showing a series of drying tumblers combined and incorporated in apparatus embodying the invention.

Referring now to the drawings, there is shown at a rotary reticulated tumbling cylinder, preferably formed of heavy wire cloth and enclosedwithin a'stationary cylindrical casing 21 of slightly larger diameter than the tumbling cylinder 20, as shown by the annular space 22, the tumbler being co-axial with the casing, so that the tumbler can free- The cylinder 20 is 1 provided with iron bands 23 at its ends and with longitudinal T- iron ribs 24 which connect the two end bands and form, a frame-work for the wire cylinder.

- The casing 21 is formed with warm air inlet apertures 25 preferably inits bottom for admission of warm air and is formed with ards 30, 31 which support the tumbler. There are two standards 30, near one end in which are journalled the two rollers 28, 28 which engage the groove in the band 27 and two standards 31, 31 near the opposite end in which are journalled the two rollers 29, 29 which engage the other peripheral raceway 27'. The two sets of rollers serve to support the tumbler. The rollers 28,28 are positively rotated and serve not only as a support but 0 also as a friction drive for the tumbler.

Preferably the tumbler is mounted on an inclined axis, that is, the inlet end of the tumbler is higher than the exit end so that there is a downward pitch from the entrance end to the exit end. Preferablythe support for one end is adjustable vertically so that the, angle of the pitch may be varied according to the rate of speed that it is desired to have the clothes travel from the inlet to the exit end. Preferably the adjustable support is at the exitendL For this purpose the standards 31 are vertically extensible or ad justable as shown in Figs. 3 and 5. To prolower end of each standard 31 has a threaded 32 whose lower end is swivelly connected to a fixture secured to the floor 33 or other support. The two screws serve as legs. By-turning the screws 32, the elevation of the outlet end of the tumbler may be raised or lowered to regulate the angle of inclination of the axis of the tumbler 'as desired. In order to to provide means for conveniently turning the screw, the shank of each screw is provided with a worm gear 34;which is engaged by a worm 35. The worms, 35 are mounted on a shaft 18, and by turning the screws said shaft may be rotated in eitlierdirection to raise or lower the standards 31.

The cylindrical casing 21 is formed with slots 36 (see Fig. 6) through which the rollers 28, 29 extend to engage the raceways 27, 27. The friction rollers 28 may be driven by any suitable means. The means shown in the drawings consists of a motor 37 which rotates a shaft 4 on which is mounted a gear 39 having driving connection with a gear 40 mounted on the shaft 41'on which the roller 28 is mount- Any other suitable driving mechanism may be employed. v

i In order to permit the variation in the elevation of the rollers 29 with relation to the rollers 28 while still keeping the gears in engagemen't, the shaft 41 is made in two secaperture therein which is engaged by a screw The clothes are fed into the tumbler at the higher end and travel through and pass out ing 21. The apertures 25 in the casing 21 communicate with the air chamber 43 and the warm dry air is admitted to the casing 21 through these aperturesand thence passes to the interior of the reticulated tumbler cylinder 20. An outlet chamber 44 extends length wise of the drier just above the casing 21, said chamber 44 fitting closely to the top of the casin g 21and being open on its lower side. The outlet apertures 26 at the top of the casing 21 open into said chamber 44. Warm air 7 is-admitted to the lower chamber 43 through a conduit 45 and the outlet chamber 44 communicates withan outlet conduit 46 for the purpose to be hereinafter described.

Annular air chambers or boxes 47 and 47 are-respectively mounted on opposite ends of the cylindrical casing 21. These annular air chambers are open to the bottom air chamber 43 and also communicate with the interior of the casing 21 through ducts 48 and 48 respectively. These ducts are inclined toward the middle part of the tumbler cylinder 20.

. As the warm air flows from the inlet chamber 43 through the apertures 25 into the annular space 22 between the casing 21 and the tumbler 20 and thence into and through the tumbler a portion of the warm air will flow from the chamber 43 into the annular chambers 47, 47 and thence through the apertures 48 in the casing to the annular space between the casing .and the cylinder, thence through the apertures in the reticulatedtumbler cylinder, thence upward across the interior of the .tumbler cylinder near its ends, thence out .which flows upwardthrough the gopds in the -.tumbler from escaping at the ends of the tumbler and causes said air to flow through the outlet conduit 46. At the same time .this' curtain of air does not interfere with the free passage of the dried clothes through the exit end of the tumbler.

Mounted within a chamber 50 is a cold water coil 51, through which fresh water flows, and there is also. a reheating coil 52.

The reheating coil may be heated by either steam, hot water, or air, or by any other suitable heating medium. The inlet warm air conduit leads from the lower part of the chamber and the outlet conduit 46 leads into a chamber 53 which connects with a blower 54, whence the air is forced into one end of'the casing 50 opposite the end from which the warm air conduit 45 leads. Within the said casing 50 near the inlet end is mounted a water pipe 55, having a series of spray nozzles 56. An air conduit '57 is mount- 'ed in the upper part of the room, preferably near the ceiling, and opens into the said chamber 53, as does also the conduit 46. The conduit 57 has a series of inlet ducts 58 through which the warm, humid air in the work room,

work ironers, presses and other apparatus, is

drawninto the chamber 53 where it mingles with the air coming through the conduit 46 from the tumbler cylinder, and thence it is forced by the blower'into the chamber 50. The air coming from these two sources is forced by the blower past the spray .nozzles 56, thence intocontact with the cold water coils, thence part of the air is sent over the heating coils 52, thence through the conduit 45, and back into the drying tumbler air chamber 43 to be used over again in the tumbler. The otherpart of theIcooled air will pass out through pipe 59 and distributed around the finishin machines and for ventilation as hereina ter described.

The water for the cold water coils 51 may be taken from any suitable supply and the heating coils may be heated in any suitable way.

The air which comes from the tumbler cylinder through the conduit 46 is usually laden with lint coming from the clothes, and there are also more or less impurities in the air that are taken in through the conduit 57. When the air from these two combined sources is forced into the chamber 50 and ast the spray nozzles 56, the lint and other oreign matter will be saturated-by the spra and will fall by gravity into a tank 68 (see ig.-4), whence it can be removed as desired. The air is thus thoroughly cleansed by the spray nozzle and then passes between and around the cold water coils 51. As it passes over the said coils 51 the air is cooled and dried, and thence passes over the heating coils 52 by which it is heated to the desired temperature and from there passes through the conduit 45 back into 80 which comes from the finishing machines, flat Y ings an electric motor 62 is provided. The

motor shaft 63 of the motor has driving connection with the fan shaft 64 through a belt 65 which runs over a pulley 66 on the motor shaft and over a pulley 67 on the fan shaft.

lVater forthe spray nozzles is supplied from the tank 68 (see Fig. 4) through ipes 69, pump 70 and pipes 71. The pump 0 is driven by a belt 17 which passes over a pulley on the fan shaft 64 and over a pulley on the pump shaft.

Means for supplying the cold water throu h the cold water coils is as follows At '72 is shown a cold water storage tank supplied through a pipe 73 from any {suitable source, such for instance as the citywvater.

system. Water from this tank passes through pipe 74, pump 7 5, and and pipes 76 to the coil 51. After the water'passes through the coil 51 in which the temperature of the water is raised by the warm I humid air passing through and around the coilfrom the drying tumbler, the water passes out through the pipes 77 to a heater, not shown, where it will be raised to a higher temperature for use in the washin machines or an other-purpose desired. If the water is not eing drawn for use it will pass through pipe 77 and through py-pass 78 into the upper part of storage tank The pump 75is driven by a belt 79 which runs over a pulley on the'fan shaft 64 and over a pulley on the pumpshaft.

. In Fig. 9 there is shown a gangof drying tumblers each supplied with warm dry air through pipes not shown leadin from the main warm air supply pipe 45. The air leaving the tumbler passes through pipes 80 to the pipe 46.

The de-humidifying, de-linting and 0001- ing'features of the apparatus are not limited to use with drying tumblers of tlretarticular type shown in the drawings and-a ready described. So far as th'esefeatures of the-apparatus are concerned, they are applicable to What I claim is: 1. A rotary drying cylinder open at each end, a cylindrical casing surroundin said drying cylinder and within which the rying I cylinder rotates, an annular air box around each end of the casing, means for conductlng warm air into the said casing and into said boxes transversely of the drying cylinder whereb an air curtain is formed across the ends 0 the cylinder and means for causing a flow of dry air into the interior of the drying cylinder.

3. A drying cylinder open at each end, an apertured casing surrounding said cylinder, an annular air box surrounding the cylinder casing at each end thereof, means for causing a flow of dry air into said annular, casing, said casing having passages through its walls 'near the ends thereof inclined toward the middle of the casing, said inclined'passages being adapted to cause the air from the annular boxes to flow toward the -middle of the cylinder.

4. drying cylinder open at each end, an apertured casing surrounding said cylinder, an annular air box surrounding the cylinder casing at each end thereof, means for causing a flow of dry air into said annular boxes and inclined passages through the lower part of the casing near the ends through which air from the annular boxes passes Into the drying cylinder and inclined passages through the upper part of the casing through which the air passes out of the dry'in cylinder and easing, said inclined passages eing inclined toward the middle of the c linder. I In testimony whereof I a ix my signature.

FRED S. BOLTZ.

use in connection with dr'yin .tumblers of other formof construction. or instance, it

. I is not necessary that the tumblersshould be reticulated or open at the ends. In fact, these features may be used in cpnnection with dry- "ing tumblers of a well known construction and so far astheclaims covering these featuresare concerned it is not intendfid to have them limited to use with drying tumblers such as are shown in the drawings. 

